French President Francois Hollande says the killing of a policeman and another individual in a Paris suburb on Monday is “unquestionably a terrorist act.”

“It was undeniably an act of terrorism, both because the perpetrator ... wanted it to be recognized as an act of terrorism, and the organization he had pledged his allegiance to also claimed the attack,” he said, referring to ISIS.

Interior Minister Bernard Cazeneuve described the late Monday killing of the senior French police officer and his partner in their home in Magnanville, near Paris, as an “abject act of terrorism.”

He said the French government is fully mobilized against the threat of terrorism, and has arrested more 100 suspects since the beginning of the current year.

The 25-year-old attacker, identified as Larossi Abballa, repeatedly stabbed the officer before taking his partner and their son hostage.

Interior Ministry spokesman Pierre-Henry Brandet said officers found the woman’s body when they stormed the house.

The assailant was shot dead by members of an elite RAID police unit after negotiations collapsed. The son was released and is under medical care.

French prosecutors have launched an anti-terror probe into the incident. Even though none of the victims was named, the 42-year-old slain police officer apparently worked in nearby Les Mureaux.

Sources close to the investigation and speaking on condition of anonymity said the attacker had claimed allegiance to ISIS while talking to officers.

The sources added that Abballa had been sentenced in 2013 for affiliation to a Takfiri network that sent recruits to Pakistan.

France has been on high alert since last November, when a total of 130 people were killed in several terrorist attacks within a matter of hours.

On Sunday, a gunman also claiming allegiance to ISIS fatally shot 49 people at a nightclub in Orlando, Florida, in the US.